UNtil = 沒到XX時(一直沒有。。),所以必須配 wasN'T UNtil .... that.... = 雙重否定 ==〉直到。。。才。如果想用 was, 則句型應該為 It was when I took the sugar away again and the tiny little current blips came back that I realized actually this was what had happened.
when 改用 after 也行,但是它後面的時間從句要改用過去完成時。不過無論 when 還是 after, 在這個情況下都不如用 wasn't until... that 來得貼切。